The relation of perception to memory is a fundamental characteristic of human cognition, each affecting and determining the other. This relation is explored empirically with a task known as priming: The primes are visually presented words or objects, or aurally presented words. In many situations the primes are irrelevant to the main task, yet nonetheless facilitate responding. In short-term priming, the primes are presented just prior to a trial, and in long-term priming many minutes prior, often in another task. The main task can be word naming, deciding whether the stimulus is a word, or matching of a test item to one or more choices presented after the trial. The ways in which the primes affect performance provide a great deal of information about the interaction of perception and memory, and about the way our knowledge is formed and modified. Models of perception, memory, and decision, have been and are being developed and tested for short-term priming (ROUSE) and long-term priming (REMI). Particular issues being explored are spatial and temporal confusions and the way the system discounts evidence for features to prevent the harmful effects of these confusions. The present project involves empirical research on a variety of these topics, coupled with theory development, to explain the results and to predict new findings. Particular emphasis in the present project is given to analysis and test of stages of perceptual processing, empirical and theoretical development of models that predict both accuracy and response time together, perceptual inference as a decision making principle, the ways that new information is added to our knowledge, and the links between episodic memory and the permanent knowledge store. The developments are aimed to contribute toward a relatively complete theory of perception, memory, and decision. [unreadable] [unreadable]